This is the VOA Special English Agriculture Report.

An agricultural official inspects a trap for evidence of the light brown apple moth in Merced County, California

California is trying to control an invasion of the light brown apple moth. The insect is native to Australia and is now found widely in New Zealand, Britain, Ireland and New Caledonia. Hawaii had them in the late eighteen hundreds, but this is the first discovery on the mainland United States.

Officials say it could cause more than one hundred thirty million dollars in crop damage and control costs if the moth spreads to agricultural production areas. California is the nation's leading agricultural state. The industry is valued at thirty-two billion dollars.

The light brown apple moth can attack more than two hundred fifty kinds of plants and trees. It causes damage by feeding on leaves, new growth and fruit, including grapes -- bad news for California's wine industry.

More than thirty thousand traps have been deployed as part of the effort to fight the invasion. As of last week the traps had caught almost five thousand light brown apple moths. The insects have been found in several counties but mostly in Santa Cruz and Monterey along the Central Coast. The others have mostly been found in the San Francisco Bay Area, to the north.

The first discovery came in February. A private citizen captured two suspicious moths in a blacklight trap on his property near Berkeley. A laboratory confirmed their identity in March. Then, in May, the United States Department of Agriculture ordered action to prevent the spread of the insect.

It restricted the movement of products including nursery plants, cut flowers and greenery from several counties in California and all of Hawaii. Shipments must be inspected and declared insect-free before they can be transported to other states.

The California Department of Food and Agriculture says growers have the choice to destroy affected plants or treat them with a chemical, chlorpyrifos. Another substance, Bt, is a natural organism used as a biological control. In June, weekly ground treatments with Bt began on more than two hundred properties in two counties, Contra Costa and Napa. Napa is famous for its wine grapes.

Control plans are being developed for the wider area, based in part on the advice of experts from Australia and New Zealand.

Mexico has suspended imports of some products from the affected areas. It also is requiring more inspection of products from outside the affected counties.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. I'm Faith Lapidus.